Clear the corner decisively and counter. Attack the ball rather than waiting for it, clear it high and away from goal, win the second ball, and exploit the space behind the committed attackers with a fast break.
Serve an inswinging corner into the box. A defender attacks the ball and heads it clear, high, far and wide, never letting it bounce. A midfielder reads the second ball and wins it at the edge, then plays a long ball to a striker who has stayed up, breaking into the space the attacking team vacated. Set marking assignments (zonal or man), a near-post defender, and a keeper who commands the box, then rehearse the clear-and-counter.
Nothing in youth football produces more goals than what happens in the six seconds after a corner is swung in, and most of those goals come from a ball that was never properly cleared. A header that goes five yards, a clearance that stays inside the box, a bounce nobody attacked: the second phase is where corners are actually lost.
The first principle is attacking the ball rather than waiting for it. A defender who steps forward to meet the delivery gets a full contact with his forehead and clears it properly. A defender who backs off and lets it come to him is heading it off the top of his head while retreating, which is how balls loop up into the six-yard box. Being on the front foot is a decision made before the ball is struck.
The second is direction. High, far and wide is the phrase worth drilling into players. Height buys time to push out. Distance takes it beyond the edge of the area where second balls are won. Width takes it away from the middle, which is the only part of the pitch where a loose ball is immediately dangerous. A clearance that satisfies two of the three is usually fine; one that satisfies none is a chance conceded.
The third is the counter, and it is the part most teams neglect entirely. An attacking side at a corner has committed six or seven players forward, which means a cleared ball meets the most exposed defensive shape they will show all match.
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